Add, subtract, multiply, and divide feet, inches, and construction fractions with fast, jobsite-friendly results.
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Add two feet + inches measurements.
12 ft 7 3/8 in + 4 ft
Construction measurements often combine feet, inches, and fractional inches. Skoppe Calculator handles the conversions automatically so measurements can be added, subtracted, multiplied, or divided without first converting everything to decimals. There are 12 inches in one foot. When adding measurements, every 12 inches carries into one additional foot. Fractional inches are combined and simplified automatically.
Total Inches = (Feet × 12) + Inches + Fraction
Perform the calculation in inches
Feet = Whole Inches ÷ 12
Remaining Inches = Total Inches − (Feet × 12)
The calculator works in exact fractions of an inch, then converts the result back into feet, inches, and a simplified fraction.
Adding 12 ft 7 3/8 in and 4 ft 9 5/8 in:
3/8 + 5/8 = 1 in
The fractions combine into a whole inch7 in + 9 in + 1 in = 17 in
17 in = 1 ft 5 in
The inches carry into 1 ft 5 in12 ft + 4 ft + 1 ft = 17 ft
Total: 17 ft 5 inFractions with different denominators are converted to a common denominator before being added.
Borrow one inch when necessary and convert it into fractional units before subtracting.
Results automatically reduce to their simplest form.
Every 12 whole inches becomes 1 additional foot.
| Measurement | Equivalent |
|---|---|
| 12 in | 1 ft |
| 1/2 in | 0.5 in |
| 1/4 in | 0.25 in |
| 1/8 in | 0.125 in |
| 1/16 in | 0.0625 in |
| 6 in | 0.5 ft |
| 3 in | 0.25 ft |
| 9 in | 0.75 ft |
Add the inches and fractional inches first, then carry every 12 inches into one additional foot. Add that amount to the feet total.
Subtract the smaller measurement from the larger one. If there are not enough inches or fractional inches to subtract directly, borrow one foot as 12 inches and continue the calculation.
Convert fractions to a common denominator, add the numerators, and simplify the result. The calculator handles this automatically.
There are 12 inches in one foot.
Divide the inches by 12 and add that value to the number of feet. For example, 6 feet 6 inches equals 6.5 feet.
Keep the whole number as feet and multiply the decimal portion by 12 to get inches. For example, 8.5 feet equals 8 feet 6 inches.
Yes. The calculator supports common construction fractions and automatically simplifies fractional results.
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